Today's search zone was the smallest yet in the month-long hunt for Malaysia Airlines Flight MH370, narrowed down to 57,923 sq km from yesterday's 75,000 sq km. The centre of the search area lies approximately 2280 kilometres north west of Perth.
Up to 10 military aircraft, four civil aircraft and 13 ships were searching for missing plane in the narrowed search zone.
Australian ship Ocean Shield towing a pinger locater in the southern Indian Ocean on Tuesday reacquired two signals after earlier detecting two on Saturday.
All of the four "pings", heard possibly from the black box of the ill-fated plane, have been recorded within approximately 27 kilometres of one another.
"I'm now optimistic. We'll find the aircraft or what's left of the aircraft in the not too distant future. Hopefully in a matter of days, we will be able to find something on the bottom that might confirm that this is the last resting place of MH370," Angus Houston, head of the Joint Agency Coordination Centre (JACC) which is leading the search, said yesterday.
Aircraft and ships reported spotting a large number of objects during yesterday's search, but only a small number were able to be recovered, the JACC said. However, none of the recovered items were believed to be associated with MH370.
In another major development yesterday, Australian authorities analysed the signals picked up on Saturday and determined that they were not natural occurrences, but likely came from specific electronic equipment. Some marine life make similar sounds.
No more signals had been picked up overnight, the search coordination centre said today.
The Ocean Shield continued its hunt towing the US navy pinger locater through the ocean's depths.
The underwater search continued today, with Ocean Shieldat the northern end of the defined search area, and Chinese shipHaixun 01and HMSEchoat the southern end, hoping to find the signal again and get a more specific fix on its location.
Finding the black box is crucial for knowing what happened on March 8 when the Beijing-bound Malaysia Airlines Boeing 777 flight MH370 with 239 people, including five Indians, disappeared under mysterious circumstances.
The batteries powering the black box are certified to be working for 30 days. Stored in a plane's tail, they are designed to begin sending off distinct, high-pitched pings or signals as soon as they come in contact with water.